Not forbidden, just not a good idea. There are automated "bots" that search websites - like forums like this - for e-mail addresses, for spamming.
If you look back through this thread, either naturally or after being advised, people will post their e-mail address as
myname @ isp . com or myname(at)isp(dot)com.
But it IS up to the person asking for the favor to provide their contact information - not for you to offer yours. And you probably know, but only always forward the entire newsletter - never just a link from it. That's per the publisher

. Who's not me.